Pulse oximetry devices in the past have utilized a sensor, generally attached to the finger, which is conductively coupled to an electronic device which actually measures and indicates the percentage of the desired constituent of arterial blood.
Examples of pulse oximeters using a conductively attached sensor would include U.S. Pat. Nos. 5,279,295; 5,035,243; 5,217,012; 5,249,576; 5,245,003; 5,209,230; 5,170,785; 5,080,098; 5,069,213; 5,041,187; 4,971,052; 4,964,408; 4,928,691; 4,865,038; 4,830,014; 4,825,879; 4,825,872; 4,770,179; 4,700,708; 4,553,498, and 4,621,643.
Applicant also has a patent on a pulse oximeter which utilizes a conductively attached sensor, U.S. Pat. No. 4,773,422, reissued as RE. 33,543. The entire contents of U.S. Pat. No. 4,773,422, issued Sep. 27, 1988 are hereby incorporated by reference. Applicant's patent pulse oximeter is embodied in several products, including the Model 8600 Portable Pulse Oximeter and the Model 8500 Hand Held Pulse Oximeter.
Despite achieving great commercial success with its line of pulse oximeters, applicant has recognized several problems with existing pulse oximeters, including their own. First, the units are still very bulky and difficult to easily transport from one location to another. These units are typically bought from patient to patient, rather than being in a stationary location. Applicants' units, particularly its hand held model 8500 are often used in connection with ambulances and are moved about a great deal. Secondly, the flexible conductive cable used by all existing pulse oximeters to attach the sensor frequently gets damaged due to being wrapped around the pulse oximeter unit during transport from one location to another. Despite many failsafes built into the cable at either end, over time the cable connections fail.
What is needed is a more portable compact pulse oximeter which eliminates the flexible conductive cable connecting the sensor to the pulse oximeter.